What
- When two or more agents would write or edit files in the same repository, the Agent tool's description can now tell Claude to give each one
isolation: "worktree". - A new
sharesCwdfield on the async agent-launch tool schema flags when another write-capable agent is already running in the same working directory. When set, the tool result for the async-launched agent includes a note about the conflict and suggests usingisolation: "worktree".
Why This helps prevent parallel agents from clobbering each other's file changes by nudging Claude toward isolating them in separate worktrees when they would otherwise write to the same directory.
Names in the bundleworktree
The entry above is what we published on the day. These lines were added later, as Anthropic's own pages caught up, and they sit beside the original rather than replacing it.
Added since
A small documentation edit on Run agents in parallel touched a line naming worktree after this was published.
* [`/batch`](/docs/en/commands) is a [skill](/docs/en/skills) that has Claude split one large change into 5 to 30 worktree-isolated subagents. It's a packaged use of subagents and worktrees, not a separate coordination style.agents see the edit
Confirmed since
Anthropic's documentation has since written up worktree, on Claude Code changelog.
* Fixed `--setting-sources` (and SDK `settingSources`) not being forwarded to spawned sessions: teammates, `/bg`, `claude agents` sessions and `--worktree --tmux` now start with the parent's restrictionchangelog see the edit
One source agreesOne thing we can check says the same as this entry.
Anthropic's documentation agrees
Anthropic's documentation has since written up worktree, on Claude Code changelog.